<!DOCTYPE html>
<html>
<script>
document.addEventListener("DOMContentLoaded", () => {
  requestAnimationFrame(() => {
    requestAnimationFrame(() => {
      document.querySelector('div').ariaHidden = true;
      requestAnimationFrame(() => {
        requestAnimationFrame(() => {
          document.documentElement.className = '';
        });
      });
    });
  });
});
</script>
<main>
  <fieldset aria-owns="owned"></fieldset>
</main>
<div>
  <footer id="owned">
    <mark>
      owned
    </mark>
  </footer>
</div>
</html>
